Antibacterial therapy with bacteriophage genotypically modified to delay inactivation by the host defense system

ABSTRACT

The present invention is directed to bacteriophage therapy, using methods that enable the bacteriophage to delay inactivation by any and all parts of the host defense system (HDS) against foreign objects that would tend to reduce the numbers of bacteriophage and/or the efficiency of those phage at killing the host bacteria in an infection. Disclosed is a method of producing bacteriophage modified for anti-HDS purposes, one method being selection by serial passaging, and the other method being genetic engineering of a bacteriophage, so that the modified bacteriophage will remain active in the body for longer periods of time than the wild-type phage.

FIELD OF THE INVENTION

The present invention relates to a method of delaying the inactivationof bacteriophages by an animal's host defense system. One method ofdelaying inactivation is the use of novel bacterio-phages whose genomeshave been modified. Methods useful for modifying the bacteriophagegenome include but are not limited to selection of mutant strains byserial passage, and the creation of new strains by genetic engineering.Such novel bacteriophages have the ability to delay being sequesteredby, engulfed by, or otherwise inactivated by one or more of theprocesses of an animal's host defense system (HDS). This novel attributeallows the “anti-HDS modified” bacteriophage to have a longer survivaltime in an animal's body than the corresponding wild-type bacteriophage,and that in turn allows the modified phage to be more effective than thewild-type phage at treating (or assisting in the treatment of) abacterial infection.

The present invention also is directed to specific methods of usingbacteriophages for treating infectious bacterial diseases. The route ofadministration can be by any means including delivering the phage byaerosol to the lungs.

BACKGROUND OF THE INVENTION

In the 1920s, shortly after the discovery of bacterial viruses(bacteriophages), the medical community began to extensively pursue thetreatment of bacterial diseases with bacteriophage therapy. The idea ofusing phage as a therapy for infectious bacterial diseases was firstproposed by d'Herelle in 1918, as a logical application of thebacteriophages' known ability to invade and destroy bacteria. Althoughearly reports of bacteriophage therapy were somewhat favorable, withcontinued clinical usage it became clear that this form of therapy wasinconsistent and unpredictable in its results. Disappointment with phageas a means of therapy grew, because the great potential of these virusesto kill bacteria in vitro was not realized in vivo. This led to adecline in attempts to develop clinical usage of phage therapy, and thatdecline accelerated once antibiotics began to be introduced in the 1940sand 50s. From the 1960s to the present, some researchers who adoptedcertain bacteriophages as a laboratory tool and founded the field ofmolecular biology have speculated as to why phage therapy failed.

Despite the general failure of phage as therapy, isolated groups ofphysicians have continued to try to use these agents to treat infectiousdiseases. Many of these efforts have been concentrated in Russia andIndia, where the high costs of and lack of availability of antibioticscontinues to stimulate a search for alternative therapies. See forexample Vogovazova et al., “Effectiveness of Klebsiella pneumoniaeBacteriophage in the Treatment of Experimental Klebsiella Infection”,Zhurnal Mikrobiologii, Epidemiologii Immunobiolocii, pp. 5-8 (April,1991); and Vogovazova et al., “Immunological Properties and TherapeuticEffectiveness of Preparations of Klebsiella Bacteriophages”, ZhurnalMikrobiologii, Epidemiolocii Immunobiologii. pp. 30-33 (March, 1992)].These articles are similar to most of the studies of phage therapy,including the first reports by d'Herelle, in that they lack many of thecontrols required by researchers who investigate anti-infectioustherapies. In addition, these studies often have little or noquantification of clinical results. For example, in the second of thetwo Russian articles cited above, the Results section concerningKlebsiella phage therapy states that “Its use was effective in . . .ozena (38 patients), suppuration of the nasal sinus (5 patients) and ofthe middle ear (4 patients) . . . In all cases a positive clinicaleffect was achieved without side effects from the administration of thepreparation”. Unfortunately, there were no placebo controls orantibiotic controls, and no criteria were given for “improvement”.

Another clinical use of phage that was developed in the 1950s and iscurrently still employed albeit to a limited extent, is the use of phagelysate, specifically staphphage lysate (SPL). The researchers in thisfield claim that a nonspecific, cell-mediated immune response to staphendotoxin is an integral and essential part of the claimed efficacy ofthe SPL. [See, eg., Esber et al., J. Immunopharmacol., Vol. 3, No. 1,pp. 79-92 (1981); Aoki et al., Augmenting Agents in Cancer Therapy(Raven, N.Y.), pp.-101-112 (1981); and Mudd et al., Ann. NY Acad. Sci.,Vol. 236, pp. 244-251 (1974).] In this treatment, it seems that thepurpose of using the phage is to lyse the bacteria specifically toobtain bacterial antigens, in a manner that those authors findpreferential to lysing by sonication or other physical/chemical means.Here again, some difficulties arise in assessing these reports in theliterature, because, in general, there are no placebo controls and nostandard antibiotic controls against which to measure the reportedefficacy of the SPL. More significantly, there is no suggestion in thesearticles to use phage per se in the treatment of bacterial diseases.Moreover, the articles do not suggest that phage should be modified inany manner that would delay the capture/sequestration of phage by thehost defense system.

Since many patients will recover spontaneously from infections, studiesmust have carefully designed controls and explicit criteria to confirmthat a new agent is effective. The lack of quantification and ofcontrols in most of the phage reports from d'Herelle on makes itdifficult if not impossible to determine if the phage therapies have hadany beneficial effect.

As there are numerous reports of attempts at phage therapy, one wouldassume that had it been effective, it would have flourished in theperiod before antibiotics were introduced. But phage therapy has beenvirtually abandoned, except for the isolated pockets mentioned above.

As noted above, some of the founders of molecular biology who pioneeredthe use of specific phages to investigate the molecular basis of lifeprocesses have speculated as to why phage therapy was not effective. Forexample, G. Stent in his book Molecular Biology of Bacterial Viruses, WHFreeman & Co. (1963) pp. 8-9, stated the following:

-   -   “Just why bacteriophages, so virulent in their antibiotic action        in vitro, proved to be so impotent in vivo, has never been        adequately explained. Possibly the immediate antibody response        of the patient against the phage protein upon hypodermic        injection, the sensitivity of the phage to inactivation by        gastric juices upon oral administration, and the facility with        which bacteria acquire immunity or sport resistance against        phage, all militated against the success of phage therapy.”

In 1973, one of the present inventors, Dr. Carl Merril, discovered alongwith his coworkers that phage lambda, administered by various routes(per os, IV, IM, IP) to germ-free, non-immune mice, was cleared out ofthe blood stream very rapidly by the organs of the reticulo-endothelialsystem, such as the spleen, liver and bone marrow. [See Geier, Trigg andMerril. “Fate of Bacteriophage Lambda in Non-Immune, Germ-Free Mice”,Nature, 246, pp.-221-222 (1973).] These observations led Dr. Merril andhis co-workers to suggest (in that same Nature article cited above)over-coming the problem by flooding the body with colloidal particles,so that the reticulo-endothelial system would be so overwhelmedengulfing the particles that the phage might escape capture. Dr. Merriland his coworkers did not pursue that approach at the time as there wasvery little demand for an alternative antibacterial treatment such asphage therapy in the 1970s, given the numerous and efficaciousantibiotics available.

Subsequently, however, numerous bacterial pathogens of great importanceto mankind have become multi-drug resistant (MDR), and these MDR strainshave spread rapidly around the world. As a result, hundreds of thousandsof people now die each year from infections that could have beensuccessfully treated by antibiotics just 4-5 years ago. [See e.g. C.Kunin, “Resistance to Antimicrobial Drugs—A Worldwide Calamity”, Annalsof Internal Medicine, 1993;118:557-561; and H. Neu, “The Crisis inAntibiotic Resistance”, Science 257, 21 Aug. 1992, pp. 1064-73.] In thecase of MDR tuberculosis, e.g., immunocompromised as well asnon-immunocompromised patients in our era are dying within the firstmonth or so after the onset of symptoms, despite the use of as many as11 different antibiotics.

Medical authorities have described multi-drug resistance not just forTB, but for a wide variety of other infections as well. Some infectiousdisease experts have termed this situation a “global crisis”. A searchis underway for alternative modes and novel mechanisms for treatingthese MDR bacterial infections.

Bacteriophage therapy offers one possible alternative treatment.Learning from the failure of bacteriophage therapy in the past, thepresent inventors have discovered effective ways to overcome the majorobstacles that were the cause of that failure.

One object of the present invention is to develop novel bacteriophageswhich are able to delay inactivation by an animal's host defense system,any component of which may be diminishing the numbers or the efficacy ofthe phage that have been administered.

Another object of the present invention is to develop a method fortreating bacterial infectious diseases in an animal by administering tothe animal an effective amount of the novel bacteriophage, and by anappropriate route of administration.

SUMMARY OF THE INVENTION

In the present invention, novel bacteriophages are developed by serialpassage or by genetic engineering, to obtain bacteriophages capable ofdelaying inactivation by any component of an animal's host defensesystem (HDS) against foreign bodies. This allows the novel phages tosurvive for longer periods of time in the circulation and the tissuesthan the wild-type phage, thereby prolonging viability and making thesemodified phages more efficient at reaching and invading the bacteria atthe site of an infection.

The administration of an anti-HDS phage that has been developed byserial passage or by genetic engineering will enable the animalrecipient to efficaciously fight an infection with the correspondingbacterial pathogen. The phage therapy of this invention will thereforebe useful either as an adjunct to standard anti-infective therapies, oras a stand-alone therapy.

The phages of the present invention can be administered by any route,such as oral, pulmonary (by aerosol or by other respiratory device forrespiratory tract infections), nasal, IV, IP, per vagina, per rectum,intra-ocular, by lumbar puncture, intrathecal, and by burr hole orcraniotomy if need be for direct insertion onto the meninges (e.g. in aheavily thickened and rapidly fatal tuberculous meningitis).

DETAILED DESCRIPTION OF THE INVENTION

One of the major obstacles to bacteriophage therapy is the fact thatwhen phages are administered to animals, they are rapidly eliminated bythe animal's HDS. That suggests that the phages are not viable in theanimal's circulation or tissues for a long enough time to reach the siteof infection and invade the bacteria. Thus, the object of the presentinvention is to develop bacteriophages that are able to delayinactivation by the HDS. This will prolong phage viability in the body.

The term “host defense system” as used herein refers to all of thevarious structures and functions that help an animal to eliminateforeign bodies. These defenses include but are not limited to the formedcells of the immune system and the humoral components of the immunesystem, those humoral components including such substances ascomplement, lysozymes and beta-lysin. In addition, the organs of whathas often been referred to as the “reticulo-endothelial system” (spleen,liver, bone marrow, lymph glands, etc.) also serve as part of the hostdefense system. In addition to all the phenomena cited just above whichtake place within this “reticulo-endothelial system”, there has alsobeen described a sequestering action wherein foreign materials(specifically including bacteriophage) are captured non-phagocyticallyand non-destructively in the spleen by what is known as theSchweigger-Seidel capillary sheaths—a phenomenon that may or may notinvolve antigen capture [See e.g. Nagy, Z., Horrath, E., and Urban, Z.,Nature New Biology, 242: p. 241 (1973).]

The phrase “substantially eliminate” as used regarding the presentinvention, indicates that the number of bacteria is reduced to a numberwhich can be completely eliminated by the animal's defense system or byusing conventional antibacterial therapies.

Enabling bacteriophages to delay inactivation by those host defensesystems—whichever components of it may or may not be employed in anygiven case—would be likely to result in an increased in vivo killing ofbacterial pathogens that are in the host range for those bacteriophages.

In one embodiment, bacteriophages are selected by serial passage. Thesewill by their nature have a delay in their inactivation by the HDS.Essentially, the serial passage is accomplished by administering thephage to an animal and obtaining serial blood samples over an extendedperiod of time. Eventually one obtains viable phage that are able todelay inactivation by the HDS. When a period is reached where in bloodsamples there remains 0.01%-1.0%, and preferably 0.1%, of the number ofphages originally placed in circulation, a sample of this remainingphage is grown up to sufficiently high titer to be injected into asecond animal of the same species. [For methods of clonal purification,see M. Adams, Bacteriophages, Interscience Publishers, pp. 454-460(1959)]. Serial blood samples are again obtained over time, and theprocess described above is repeated iteratively so that each time whenapproximately 0.1% of the phages are left, it takes longer and longerwith each serial passage to reach that point when only 0.1% of the phageadministered still remain in circulation. By this method of clonalpurification and selection, a phage strain will be isolated that cansurvive at least 15% longer in the body than the longest-survivingwild-type phage.

After a number of serial passages of these non-mutagenized ormutagenized (see below) bacteriophage, a prototype “anti-HDS modified”bacteriophage is obtained. As used herein, an “anti-HDS modified” phageis defined as any phage (whether modified by serial passage or bygenetic engineering) that has a half-life within the animal that is atleast 15% greater than the half-life of the original wild-type phagefrom which it was derived. Half-life refers to the point in time whenout of an initial IV dose (e.g. 1×10¹²) of a given phage, half (1×10⁶)of them still remain in circulation, as determined by serial pfuexperiments (“pfu” meaning plaque forming units, a convenient measure ofhow many phage are present in a given sample being assayed). A 15%longer half-life indicates a successful delay of inactivation by theHDS.

The evidence that the HDS-evading phages do in fact remain viable for alonger period of time in the body is obtained by demonstrating not onlyby the longer time that they remain in the circulation, but also by thehigher numbers of them that remain in the circulation at a given pointin time. This slower rate of clearance is demonstrated by the fact thatten minutes after the IV injection of 1×10¹² of the phages into a testanimal, the number of the phages still in circulation (as measured bypfu assays) is at least 10% higher than the number of the correspondingwild-type phage still in circulation in the control animal, at thatpoint in time.

Instead of awaiting the spontaneous mutations that are selected for inthe above method, alternatively mutations can be provoked during thegrowth of the phage in its host bacteria. The mutations may producespecimens of phage that, after selection by serial passage, are evenmore efficient than the non-mutagenized phage at delaying inactivationby the host defense system. Mutagenization is achieved by subjecting thephage to various stimuli, such as, but not limited to, acridinecompounds, ethidium bromide in the presence of light, radioactivephosphorus, and various forms of radiation (X-rays, UV light, etc.).Mutants resulting from the iterative procedure described above, and thatare found to have a longer survival time than the wild-type phage, aregrown to high titer and are used to treat infectious diseases in animalsand in humans.

The phage obtained by the above methods are referred to as “anti-HDSselected”.

An altogether different method to achieve the desired result is togenetically engineer a phage so that it expresses molecules on itssurface coat, where said molecules antagonize, inactivate, or in someother manner impede those actions of the HDS that would otherwise reducethe viability of the administered phages. One of the ways to accomplishthis is to engineer a phage to express molecules that antagonize one ormore of the complement components.

Complement components fix to bacteriophages, and these bacteriophagesthen adhere to certain white blood cells (such as macrophages) thatexpress complement receptors. Numerous peptides have been synthesizedthat antagonize the functions of the various complement components. [Seee.g. Lambris, J. D. et al, “Use of synthetic peptides in exploring andmodifying complement reactivities” in Activators and Inhibitors ofComplement, ed. R. Sim, Kluwer Academic Publishers, Boston, 1993.]Lambris et al. (op.cit.) cite “a series of synthetic peptides spanningthe covertase cleavage site in C3 (that are) found to inhibit complementactivation by both the classical and alternative pathways”. Among thepeptides cited is a six amino acid peptide (LARSNL, residues 746-751 ofC3) that “inhibits both pathways equally well”.

In one method of genetically engineering such a phage, a fusion proteinis obtained, wherein the peptide will be bound to the carboxyl end ofthe surface protein of interest [See e.g. Sambrook, J., Fritsch, E., andManiatis, T.: Molecular Cloning. A Laboratory Manual, 2nd Ed., ColdSpring Harbor Laboratory Press, Cold Spring Harbor, N.Y., 1989]. Thisconstruct is made by cloning the gene for the phage surface protein intoa plasmid vector system, and then cloning the oligonucleotide for thepeptide of interest into this carrying vector by in-frame fusion at the3′-end of the gene for the surface protein. This fusion of the gene forthe phage surface protein with the oligonucleotide for thecomplement-antagonizing peptide would then be incorporated into thephage of interest by the in vivo generalized recombination system in thehost bacteria for the phage of interest. Phage whose genomic sequence isalready completely known, and phage whose genomic sequence is unknown orpartially unknown can be used in the present invention.

The surface expression of a recombinant complement-antagonizing peptideis but one example of several complement-related strategies that mightbe used for these purposes. Another example would be the expression of ahuman complement-antagonizing protein on the surface of a phage. Severaltransplantation research facilities are currently expressing such humancomplement-antagonizing proteins in transgenic animals, in the hopesthat when these transgenic organs are donated they will not beimmunologically rejected by a human recipient. [See e.g. GeneticEngineering News, Oct. 15, 1993, p.1.] In an analogous manner, theexpression of such recombinant human complement-antagonizing proteins onthe surface of a bacteriophage may allow the phage to delay beinginactivated by the host defense system.

In addition to complement-related strategies, there are many othercategories of molecules that can be recombinantly engineered into aphage to delay inactivation by the host's defense system. Othercategories of molecules that could be expressed on the surface ofbacteriophages, and would fall under the scope of this invention,include but are not limited to: interleukins and other cytokines;autocrines; and inhibitors of the various cellular activating orinhibiting factors (e.g. inhibitors of macrophage activating factor).Genes for these proteins (or for active subunits of them) can beincorporated into a phage genome so that they will be expressed on thesurface.

In addition, if it were possible to get a given bacterial host strain toglycosylate a recombinant protein, then the purpose of the inventioncould be served by introducing genes that will express glycosylatedproteins. Such proteins are known by their negative charge to repelimmune cells, such as the macrophage. Examples might include but wouldnot be limited to (1) the C-terminal portion of the β-subunit of humanchorionic gonadotrophin (hCG), and (2) the various glycophorins on thesurfaces of blood cells.

Phage modified in this manner are referred to as “anti-HDS engineered”.

The present invention can be applied across the spectrum of bacterialdiseases, either by serial passage of phages (mutagenized ornon-mutagenized) or by genetically engineering phages, so that phagesare developed that are specific for each of the bacterial strains ofinterest. In that way, a full array of anti-HDS selected and/or anti-HDSengineered bacteriophage is developed for virtually all the bacterial(and other applicable) pathogens for man, his pets, livestock and zooanimals (whether mammal, avian, or pisciculture). Phage therapy willthen be available:

-   -   1) as an adjunct to or as a replacement for those antibiotics        and/or chemotherapeutic drugs that are no longer functioning in        a bacteriostatic or bactericidal manner due to the development        of multi-drug resistance;    -   2) as a treatment for those patients who are allergic to the        antibiotics and/or chemotherapeutic drugs that would otherwise        be indicated; and    -   3) as a treatment that has fewer side effects than many of the        antibiotics and/or chemotherapeutic drugs that would otherwise        be indicated for a given infection.

The second embodiment of the present invention is the development ofmethods to treat bacterial infections in animals through phage therapywith the anti-HDS modified bacteriophages described above. Hundreds ofbacteriophages and the bacterial species they infect are known in theart. The present invention is not limited to a specific bacteriophage ora specific bacteria. Rather, the present invention can be utilized todevelop anti-HDS modified bacteriophages which can be used to treat anyand all infections caused by their host bacteria.

While it is contemplated that the present invention can be used to treatany bacterial infection in an animal, it is particularly contemplatedthat the methods described herein will be very useful as a therapy(adjunctive or stand-alone) in infections caused by drug-resistantbacteria. Experts report [See e.g. Gibbons, A., “Exploring NewStrategies to Fight Drug-Resistant Microbes, Science, 21 Aug. 1993, pp.1036-38.] that at the present time, the drug-resistant bacterial speciesand strains listed below represent the greatest threat to mankind:

-   -   1. All of the clinically important members of the family        Enterobacteriaceae, most notably but not limited to the        following:        -   a) All the clinically important strains of Escherichia, most            notably E. coli. One among a number of candidate wild-type            phages against these particular., pathogens that could be            used as a starting point for the serial passage and/or the            genetic engineering of the present invention would be ATCC            phage # 23723-B2. [Note: For purposes of brevity, in all the            following examples of pathogens, the corresponding wild-type            phage will be indicated by the following phraseology:            “Example of corresponding phage: ______ “.]        -   b) All the clinically important strains of Klebsiella, most            notably K. pneumoniae [Example of corresponding phage: ATCC            phage # 23356-B1].        -   c) All the clinically important strains of Shigella, most            notably S. dysenteriae [Example of corresponding phage: ATCC            phage # 11456a-B1].        -   d) All the clinically important strains of Salmonella,            including S. abortus-ecui (Example of corresponding phage:            ATCC phage # 9842-B1], S. typhi [Example of corresponding            phage: ATCC phage # 19937-B1], S. typhimurium [Example of            corresponding phage: ATCC phage # 19585-B1], S. newport            [Example of corresponding phage: ATCC phage # 27869-B1], S.            paratyphi-A (Example of corresponding phage: ATCC phage #            12176-B1], S. paratyphi-B (Example of corresponding phage:            ATCC phage # 19940-B1], S. potsdam (Example of corresponding            phage: ATCC phage-# 25957-B2], and S. pollurum [Example of            corresponding phage: ATCC phage # 19945-B1].        -   e) All the clinically important strains of Serratia, most            notably S. marcescens [Example of corresponding phage: ATCC            phage # 14764-B1].        -   f) All the clinically important strains of Yersinia, most            notably Y. pestis [Example of corresponding phage: ATCC            phage # 11953-B1].        -   g) All the clinically important strains of Enterobacter,            most notably E. cloacae [Example of corresponding phage:            ATCC phage # 23355-B1].    -   2. All the clinically important Enterococci, most notably E.        faecalis [Example of corresponding phage: ATCC phage # 19948-B1]        and E. faecium [Example of corresponding phage: ATCC phage        #19953-B1].    -   3. All the clinically important Haemophilus strains, most        notably H. influenzae (a corresponding phage is not available        from ATCC for this pathogen, but several can be obtained from        WHO or other labs that make them available publicly].    -   4. All the clinically important Mycobacteria, most notably M.        tuberculosis [Example of corresponding phage: ATCC phage #        25618-B1], M. avium-intracellulare, M. bovis, and M. leprae.        [Corresponding phage for these pathogens are available        commercially from WHO, via The National Institute of Public        Healthy & Environmental Protection, Bilthoven, The Netherlands].    -   5. Neisseria gonorrhoeae and N. meningitidis [Corresponding        phage for both can be obtained publicly from WHO or other        sources].    -   6. All the clinically important Pseudomonads, most notably P.        aeuruginosa (Example of corresponding phage: ATCC phage #        14203-B1].    -   7. All the clinically important Staphylococci, most notably S.        aureus [Example of corresponding phage: ATCC phage # 27690-B1]        and S. epidermidis [Corresponding phage are available publicly        through the WHO, via the Colindale Institute in London].    -   8. All the clinically important Streptococci, most notably S.        pneumoniae [Corresponding phage can be obtained publicly from        WHO or other sources].    -   9. Vibrio cholera [Example of corresponding phage: ATCC phage #        14100-B1].

There are additional bacterial pathogens too numerous to mention that,while not currently in the state of antibiotic-resistance crisis,nevertheless make excellent candidates for treatment with anti-HDSmodified bacteriophages that are able to delay inactivation by the HDS,in accordance with the present invention. Thus, all bacterial infectionscaused by bacteria for which there is a corresponding phage can betreated using the present invention.

Any phage strain capable of doing direct or indirect harm to a bacteria(or other pathogen) is contemplated as useful in the present invention.Thus, phages that are lytic, phages that are lysogenic but can laterbecome lytic, and nonlytic phages that can deliver a product that willbe harmful to the bacteria are all useful in the present invention.

The animals to be treated by the methods of the present inventioninclude but are not limited to man, his domestic pets, livestock,pisciculture, and the animals in zoos and aquatic parks (such as whalesand dolphins).

The anti-HDS modified bacteriophage of the present invention can be usedas a stand-alone therapy or as an adjunctive therapy for the treatmentof bacterial infections. Numerous antimicrobial agents (includingantibiotics and chemotherapeutic agents) are known in the art whichwould be useful in combination with anti-HDS modified bacteriophage fortreating bacterial infections. Examples of suitable antimicrobial agentsand the bacterial infections which can be treated with the specifiedantimicrobial agents are listed below. However, the present invention isnot limited to the antimicrobial agents listed below as one skilled inthe art could easily determine other antimicrobial agents useful incombination with anti-HDS modified bacteriophage. Pathogen Antimicrobialor antimicrobial group E. coli uncomplicated urinarytrimethoprim-sulfamethoxazole tract infection (abbrev. TMO-SMO), orampicillin; 1st generation cephalosporins, ciprofloxacin systemicinfection ampicillin, or a 3rd generation cephalosprorin;aminoglycosides, aztreonam, or a penicillin + a pencillinase inhibitorKlebsiella pneumoniae 1st generation cephalosporins; 3rd gener.cephalosporins, cefotaxime, moxalactam, amikacin, chloramphenicolShigella (various) ciprofloxacin; TMO-SMO, ampicillin, chloramphenicolSalmonella: S. typhi chloramphenicol; ampicillin or TMO-SMO non-typhispecies ampicillin; chloramphenicol, TMO-SMO, ciprofloxacin Yersiniapestis streptomycin; tetracycline, chloramphenicol Enterobacter cloacae3rd generation cephalosporins, gentamicin, or tobramycin; carbenicillin,amikacin, aztreonam, imipenem Hemophilus influenzae: meningitischloramphenicol or 3rd generation cephalosporins; ampicillin other H.infl. infections ampicillin; TMO-SMO, cefaclor, cefuroxime,ciprofloxacin Mycobacterium tuberculosis isoniazid (INH) + rifampin orand M. avium-intracellulare rifabutin, the above given along withpyrazinamide +/or ethambutol Neisseria: N. meningitidis penicillin G;chloramphenicol, or a sulfonamide N. gonorrhoeae: penicillin-sensitivepenicillin G; spectinomycin, ceftriaxone penicillin-resistantceftriaxone; spectinomycin, cefuroxime or cefoxitin, ciprofloxacinPseudomonas aeruginosa tobramycin or gentamycin (+/−carbenicillin,aminoglycosides); amikacin, ceftazidime, aztreonam, imipenem Staphaureus non-penicillinase penicillin G; 1st generation producingcephalosporins, vancomycin, imipenem, erythromycin penicillinaseproducing a penicillinase-resisting penicillin; 1st generationcephalosporins, vancomycin, imipenem, erythromycin Streptococcuspneumoniae penicillin G; 1st generation cephalosporins, erythromycin,chloramphenicol Vibrio cholera tetracycline; TMO-SMO

The routes of administration include but are not limited to: oral,aerosol or other device for delivery to the lungs, nasal spray,intravenous, intramuscular, intraperitoneal, intrathecal, vaginal,rectal, topical, lumbar puncture, intrathecal, and direct application tothe brain and/or meninges. Excipients which can be used as a vehicle forthe delivery of the phage will be apparent to those skilled in the art.For example, the free phage could be in lyophilized form and bedissolved just prior to administration by IV injection. The dosage ofadministration is contemplated to be in the range of about 10⁶ to about10¹³ pfu/per kg/per day, and preferably about 10¹² pfu/per kg/per day.The phage are administered until successful elimination of thepathogenic bacteria is achieved.

With respect to the aerosol administration to the lungs, the anti-HDSmodified phage is incorporated into an aerosol formulation specificallydesigned for administration to the lungs by inhalation. Many suchaerosols are known in the art, and the present invention is not limitedto any particular formulation. An example of such an aerosol is theProventiltm inhaler manufactured by Schering-Plough, the propellant ofwhich contains trichloromonofluoromethane, dichlorodifluoromethane andoleic acid. The concentrations of the propellant ingredients andemulsifiers are adjusted if necessary based on the phage being used inthe treatment. The number of phage to be administered per aerosoltreatment will be in the range of 10⁶ to 10¹³ pfu, and preferably 10¹²pfu.

The foregoing embodiments of the present invention are further describedin the following Examples. However, the present invention is not limitedby the Examples, and variations will be apparent to those skilled in theart without departing from the scope of the present invention. Inparticular, any bacteria and phage known to infect said bacteria can besubstituted in the experiments of the following examples.

EXAMPLES Example 1

Selection of anti-HDS selected phage by serial passage through mice

Part 1. A stock of mutagenized or non-mutagenized lambda coliphagestrain is injected in one bolus into the blood of laboratory mice at10¹² pfu/per kg, suspended in 0.5 cc of sterile normal saline. The miceare periodically bled to follow the survival of the phage in the body.The phage are assayed by plating them on their laboratory host, E. coli.When the titer of phage in the mice reaches a range of 0.01%-1.0%, andpreferably 0.1%, of the titer initially injected, the phage isolated atthis point in time are plaque isolated and the procedure repeated. Therepeated passage of the lambda phage between animal and bacteria yieldsa phage strain that has a longer survival time in the body of the mice.The anti-HDS selected phage strain is then subjected to clonal (plaque)purification.

Where the phage being administered for serial passage have first beenmutagenized, the mutagenization is carried out according to proceduresknown in the art [See e.g., Adams, M. Bacteriophages. N.Y.: WileyInterscience, 1959, pp. 310-318 and pp. 518-520.] For mutagenization byultraviolet radiation, during the last 40%-90% (and preferably 65%) ofthe latent period, the phage (inside the infected host bacteria) areexposed to 3,000-6,000 ergs (and preferably 4,500 ergs) of ultravioletradiation per square mm. For mutagenization by X-radiation, a wavelengthof 0.95 Å is used at doses from 10-250 (and preferably 150)kiloroentgens.

Example 2

Determination that HDS inactivation is delayed for the anti-HDS selectedphage as compared to wild-Type Phage

Two groups of mice are injected with phage as specified below:

-   -   Group 1: The experimental group receives an IV injection        consisting of 1×10¹² of the anti-HDS selected phage, suspended        in 0.5 cc of normal sterile saline.    -   Group 2: The control group receives a IV injection consisting of        1×10¹² of the wild-type phage from which the serially-passaged        phage were derived, suspended in 0.5 cc of sterile normal        saline.

Both groups of mice are bled at regular intervals, and the blood samplesassayed for phage content (by pfu assays) to determine the following:

-   -   1) Assays for half-lives of the two phages: For each group of        mice, the point in time is noted at which there remains in        circulation only half (i.e., 1×10⁶) the amount of phage as        administered at the outset. The point in time at which half of        the anti-HDS selected phage have been eliminated from the        circulation is at least 15% longer than the corresponding point        in time at which half of the wild-type phage have been        eliminated from the circulation.    -   2) Assays for absolute numbers: For each group of mice, a sample        of blood is taken at precisely 1 hour after administration of        the phage. At 1 hour post-injection, the numbers of        anti-HDS-selected phage in circulation are at least 10% higher        than the numbers of wild-type phage still in circulation.

Example 3

Determination that the anti-HDS selected phage has a greater capacitythan wild-type phage to prevent lethal infections in mice.

Part 1. Peritonitis Model: An LD₅₀ dosage of E. coli is administeredintraperitonally (IP) to laboratory mice. The strain of E. coli used isknown to be lysed by the coliphage strain that is selected by SerialPassage. The treatment modality is administered precisely 20 minutesafter the bacteria are injected, but before the onset of symptoms. Thetreatment modalities consist of the following:

-   -   Group 1: The experimental group receives an IP injection        consisting of 1×10¹² of the anti-HDS selected phage lambda        coliphage suspended in 2 cc of sterile normal saline.    -   Group 2: A first control group receives an IP injection        consisting of 1×10¹² of the wild-type phage from which the        anti-HDS selected phage were developed, suspended in 2 cc of        normal sterile saline.    -   Group 3: A second control group receives an IP injection of 2 cc        of normal sterile saline.

Evidence that treatment with the anti-HDS selected phage prevented thedevelopment of a lethal event in the peritonitis model is measured byusing the following three criteria:

-   -   (1) Survival of the animal    -   (2) Bacterial counts: Samples of peritoneal fluid are withdrawn        every ½ hour from the three groups of infected mice, and the        rate of increase or decrease in E. coli colony counts in the        three groups is noted    -   (3) Phage control: Using the samples of IP fluid withdrawn from        the infected mice, the numbers of pfu of the anti-HDS selected        phage and the numbers of pfu of the wild-type phage are noted.        Part 2. Bacteremia Model:

An LD₅₀ dosage of E. coli is administered intravenously (IV) tolaboratory mice, where the strain of E. coli used is known to be lysedby the coliphage strain that was chosen for the serial passage. Thetreatment modality (see below) is administered precisely 20 minutesafter the bacteria are injected, but before the onset of symptoms. Thetreatment modalities consist of the following:

-   -   Group 1: The experimental group receives an IV injection        consisting of 1×10¹² of the anti-HDS selected lambda coliphage        suspended in 0.5 cc of sterile normal saline.    -   Group 2: A first control group receives an IV injection        consisting of 1×10¹² of the wild-type phage from which the        Anti-HDS selected phage were developed, suspended in 0.5 cc of        normal sterile saline.    -   Group 3: A second control group receives an IV injection of 0.5        cc of normal sterile saline.

Evidence that treatment with the anti-HDS selected phage prevented thedevelopment of a lethal event in the bacteremia model is measured usingthe following three criteria:

-   -   (1) Survival of the animal    -   (2) Bacterial counts: Samples of blood are withdrawn every ½        hour from the three groups of infected mice, and the rate of        increase or decrease in E. coli colony counts in the three        groups is noted.    -   (3) Phage counts: In the samples of blood withdrawn from the        infected mice, the numbers of pfu of the anti-HDS selected phage        and the numbers of pfu of the wild-type phage are noted.

Example 4

Genetic engineering of phage to express molecules that antagonize thehost defense system, thereby enabling the phage to delay inactivation bythe host defense system.

Part 1. Making the Fusion Protein

Step 1. A double-stranded DNA encoding the complement antagonizingpeptide LARSNL is synthesized on an automated oligonucleotidesynthesizer using standard techniques.

Step 2. The gene for the phage coat surface protein of interest (seepart 2, below) is cloned into a plasmid vector system, by techniquesknown in the art. The oligonucleotide that has been prepared in Step 1is cloned into the plasmid vector system by in-frame fusion at the3′-end of the gene for the surface protein.

Step 3. The fusion gene is then incorporated into a phage by the in vivogeneralized recombination system in the host bacteria for the phage. Thephage then expresses the fusion protein on its surface.

Part 2: Selecting phage coat surface proteins for fusion with thepeptide/protein of interest.

A. Incorporating the Gene for the Complement-Antagonizing Peptide Into aPhage Whose Genome is Well Characterized

The orfx gene, which encodes a carboxy-terminal tail protein of lambdacoliphage, is one for which it is known that foreign nucleotidesequences can be introduced without there being disruption of thestructure or function of the phage. The tail surface protein expressedby the orfx gene is made into a fusion protein with thecomplement-antagonizing peptide, by the plasmid vector method describedin part 1 above.

B. Incorporating a Gene for a Complement-antagonizing Peptide Into aPhage Whose Genome is not Well Characterized.

Step 1. Selection of the phage surface protein to be fused with thecomplement-antagonizing peptide:

-   -   a) Isolation of phage coat surface proteins and preparation of        antibodies thereto:        -   (1) Samples of the phage of interest are broken up in 0.1%            SDS detergent for 2 minutes at 95° C. The mixture is cooled            and placed in 9M urea, and is then separated by high            resolution 2D gel electrophoresis. The protein fragments are            then isolated from the gel, and processed as described            below.        -   (2) Samples of the protein fragments from the gel are            injected into animals to produce either polyclonal or            monoclonal antibodies.        -   (3) Antibodies are isolated and then marked with uranium.            These marked antibodies are reacted against whole phage. The            marker pinpoints precisely those proteins on the surface of            the phage to which the antibodies have bound through            visualization by electronmicroscopy. [See e.g. K. Williams            and M. Chase, ed., Methods In Immunology and            Immunochemistry, Vol.1, 1967, Academic Press.] Antibodies            directed against a surface protein extending outward from            the surface of the virus are retained for further use.    -   b) Preparation of phage restriction fragments:

The genome of the phage is cut by restriction enzymes, and the resultingrestriction fragments are cloned into expression vector plasmids. Eachof these plasmids expresses its corresponding protein, creating a poolof expressed proteins.

-   -   c) Reacting the expressed proteins with the marked antibodies:

The antibodies directed against a surface protein extending outward fromthe surface of the virus are reacted against the proteins expressed bythe plasmid vectors.

-   -   d) Correlating coat protein antibodies to the plasmid vectors        that express the genes for those coat proteins:

The reaction of a marked antibody with an expressed protein pinpointsthe expression plasmid whose enclosed restriction fragment expresses theparticular protein. Thus, the genomic fragment encoding each coatsurface protein is determined using the marked antibodies.

-   -   e) Determining that the gene in its entirety has been obtained:

The restriction fragments containing a gene for a surface protein aremicro-sequenced by the Sanger technique to determine (1) the preciseamino acid sequence of the coat surface proteins; (2) the presence of astart and a stop signal (indicating that the gene in its entirety hasbeen obtained) ; and (3) the presence of either a C-terminal or anN-terminal amino acid.

Step 2. Fusing the candidate phage surface protein with thecomplement-antagonizing peptide of interest:

-   -   a) Preparing the coat protein gene for fusion:

The gene for a surface protein is contained in its plasmid expressionvector. The oligo-nucleotide for the complement-antagonizing peptide isspliced into this plasmid expression vector by in-frame fusion at the3′-end of the coat surface protein.

-   -   b) Incorporating the fusion gene into the phage of interest:

The fusion gene is incorporated into the phage by the in vivogeneralized recombination system in the host bacteria for the phage.

-   -   c) Demonstrating that the phage expresses the fusion protein:

The phage is incubated with a corresponding heavy metal-marked antibodythat has been raised against the coat surface protein. The marker isdetected on the phage by electronmicroscopy only if the phage hasexpressed that fusion protein on its surface. [See e.g. K. Williams andM. Chase, Methods In Immunology and Immunochemistry, Vol.1, 1967,Academic Press.]

Example 5

Demonstration that the genetically engineered phage delay inactivationby the HDS, compared to wild-type phage:

Two groups of mice are injected with phage as specified below:

-   -   Group 1: The experimental group receives an IV injection        consisting of 1×10¹² of the genetically modified phage,        suspended in 0.5 cc of sterile normal saline.    -   Group 2: The control group receives an IV injection consisting        of 1×10¹² of the wild-type phage from which the genetically        modified phage were derived, suspended in 5 cc of sterile normal        saline.

Both groups of mice are bled at regular intervals, and the blood samplesassayed for phage content (by pfu assays) to determine the following:

-   -   1) Assays for half-lives of the two phages: For each group of        mice, the point in time is noted at which there remains in        circulation only half (i.e., 1×10⁶) the amount of phage as        administered at the outset. The point in time at which half of        the genetically modified phage have been eliminated from the        circulation is at least 15% longer than the corresponding point        in time at which half of the wild-type phage have been        eliminated from the circulation.    -   2) Assays for absolute numbers: For each group of mice, a sample        of blood is taken at precisely 1 hour after administration of        the phage. The criterion used is that at l hour post-injection,        pfu assays reveal that the numbers of genetically engineered        phage still in circulation in the experimental animal are at        least 10% higher than the numbers of wild-type phage still in        circulation in the control animal.

Example 6

Determination that the genetically engineered phage has a greatercapacity than wild type phage to prevent lethal infections in mice.

Part 1. Peritonitis Model:

An LD₅₀ dosage of E. coli is administered intraperitonally (IP) tolaboratory mice. The strain of E. coli used is one known to be lysed bythe coliphage strain that has been genetically engineered. The treatmentmodality is administered precisely 20 minutes after the bacteria areinjected, but before the onset of symptoms. The treatment modalitiesconsist of the following:

-   -   Group 1: The experimental group receives an IP injection        consisting of 1×10¹² of the genetically engineered lambda        coliphage suspended in 2 cc of sterile normal saline.    -   Group 2: A first control group receives an IP injection        consisting of 1×10¹² of the wild-type phage from which the        genetically modified phage were developed, suspended in 2 cc of        sterile normal saline.    -   Group 3: A second control group receives an IP injection of        sterile normal saline.

Evidence that treatment with the genetically modified phage preventedthe development of a lethal event in the peritonitis model is measuredby using the following three criteria:

-   -   (1) Survival of the animal    -   (2) Bacterial counts: Samples of peritoneal fluid are withdrawn        every ½ hour from the three groups of infected mice, and the        rate of increase or decrease in E. coli colony counts in the        three groups is noted    -   (3) Phage control: Using the samples of IP fluid withdrawn from        the infected mice, the numbers of pfu of the genetically        engineered phage versus the numbers of pfu of the wild-type        phage are noted.        Part 2. Bacteremia Model:

An LD₅₀ dosage of E. coli is administered intravenously (IV) tolaboratory mice, where the strain of E. coli used is known to be lysedby the coliphage strain that was genetically engineered. The treatmentmodality (see below) is administered precisely 20 minutes after thebacteria are injected, but before the onset of symptoms. The treatmentmodalities consist of the following:

-   -   Group 1: The experimental group receives an IV injection        consisting of 1×10¹² of the genetically engineered lambda        coliphage suspended in 0.5 cc of sterile normal saline.    -   Group 2: A first control group receives an IV injection        consisting of 1×10¹² of the wild-type phage from which the        genetically engineered phage were developed, suspended in 0.5 cc        of sterile normal saline.    -   Group 3: A second control group receives an IV injection of 0.5        cc of sterile normal saline.

Evidence that treatment with the genetically engineered phage preventedthe development of a lethal event in the bacteremia model is measuredusing the following three criteria:

-   -   (1) Survival of the animal    -   (2) Bacterial counts: In the samples of blood that are withdrawn        every 1/2 hour from the three groups of infected mice, the        absolute numbers as well as the rate of increase or decrease        in E. coli colony counts is noted, for each of those three        groups.    -   (3) Phage counts: In the samples of blood withdrawn from the        infected mice, the numbers of pfu of the genetically engineered        phage and the numbers of pfu of the wild-type phage are noted.

1. A method for treating an infectious disease caused by a bacteria, inan animal, comprising: administering to an animal in need of suchtreatment, a lytic or non-lytic bacteriophage that is specific for saidbacteria in a dosage effective to substantially eliminate the bacteria,wherein said bacteriophage has a genetically inheritable ability todelay inactivation by an animal's host defense system.
 2. The methodaccording to claim 1, wherein said bacteria is a drug resistantbacteria.
 3. The method according to claim 1, wherein said animal is nota mammal.
 4. The method according to claim 1, wherein said animal is amammal.
 5. The method according to claim 4, wherein said mammal is ahuman.
 6. The method according to claim 1, wherein said bacteriophagehas at least a 15% longer half-life than a corresponding wild-typephage.
 7. The method according to claim 1, wherein the bacteriophage isobtained by anti-HDS selection (serial passage) of a mutagenized ornon-mutagenized bacteriophage which is able to survive in an animal fora longer period than a corresponding wild-type bacteriophage.
 8. Themethod according to claim 1, wherein the bacteria is selected from thegroup consisting of Mycobacteria, Staphylococci, Vibrio, Enterobacter,Enterococci, Escherichia, Haemophilus, Neisseria, Pseudomonas, Shigella,Serratia, Salmonella and Streptococci, and the bacteriophage caneffectively lyse the bacteria.
 9. The method according to claim 8,wherein the bacteria is selected from the group consisting of M.tuberculosis, M. avium-intracellulare and M. bovis.
 10. The methodaccording to claim 1, wherein the bacteriophage is administered byway ofan aerosol to an animal's lungs.
 11. The method according to claim 1,wherein the bacteriophage is administered at a dosage of about 10⁶ toabout 10¹³ pfu/kg/day.
 12. The method according to claim 11, wherein thebacteriophage is administered at a dosage of about 10¹² pfu/kg/day. 13.An isolated and purified bacteriophage that has a geneticallyinheritable ability to delay inactivation by an animal's host defensesystem.
 14. The bacteriophage according to claim 13, wherein saidbacteriophage has at least a 15% longer half-life than a correspondingwild-type phage.
 15. The bacteriophage according to claim 13, whereinthe bacteriophage is obtained by anti-HDS selection of a bacteriophagethat is able to survive in an animal's body longer than thecorresponding wild-type bacteriophage.
 16. The bacteriophage accordingto claim 13, wherein the bacteriophage is obtained by geneticengineering of an anti-HDS bacteriophage that is able to survive in ananimal's body longer than the corresponding wild-type bacteriophage. 17.The bacteriophage according to claim 13, wherein said phage is specificfor bacterial families selected from the group consisting ofEscherichia, Klebsiella, Shigella, Salmonella, Serratia, Yersinia,Enterobacter, Enterococci, Haemophilus, Mycobacteria, Neisseria,Pseudomonas, Staphylococci, Streptococci and Vibrio.
 18. A method ofobtaining a bacteriophage that is able to delay inactivation by ananimal's host defense system against foreign bodies, comprising: (a)intravenously injecting a bacteriophage into an animal; (b) obtainingserial blood samples over time and measuring the bacteriophage presentin each sample; (c) growing a portion of a sample obtained when about0.1% to 1% of the bacteriophage remain in said animal, to high titer ina host bacteria; and (d) repeating steps (a), (b) and (c) at least once,to yield an “anti-HDS” bacteriophage that has delayed inactivation by ananimal's host defense system.
 19. The method according to claim 18,wherein step (d) is repeated until a bacteriophage is obtained which hasat least a 15% longer half-life than a corresponding wild-type phage.20. A method of producing a bacteriophage able to delay inactivation byan animal's host, defense system, comprising genetically engineering abacteriophage to express molecules on its surface coat that delayinactivation of the bacteriophage by an animal's host defense system.21. The method according to claim 1, wherein the bacteriophage isobtained by genetic engineering.
 22. The method according to claim 20,wherein the bacteria is selected from the group consisting ofMycobacteria, Staphylococci, Vibrio, Enterobacter, Enterococci,Escherichia, Haemophilus, Neisseria, Pseudomonas, Shigella, Serratia,Salmonella and Streptococci, and the bacteriophage can effectively lysethe bacteria.
 23. The method according to claim 22, wherein the bacteriais selected from the group consisting of M. tuberculosis, M.avium-intracellulare and M. bovis.
 24. The method according to claim 20,wherein the bacteriophage is administered by way of an aerosol to ananimal's lungs.
 25. The method according to claim 20, wherein thebacteriophage is administered at a dosage of about 10⁶ to about 10¹³pfu/kg/day.
 26. The method according to claim 25, wherein thebacteriophage is administered at a dosage of about 10¹² pfu/kg/day. 27.A method for treating an infectious disease caused by a bacteria,comprising administering to an animal in need of such treatment anantibiotic and/or a chemotherapeutic agent in combination with abacteriophage specific for said bacteria, in a dosage effective tosubstantially eliminate the bacteria, wherein said bacteriophage has agenetically inheritable ability to delay inactivation by the animal'shost defense system.
 28. A pharmaceutical composition comprising anisolated and purified bacteriophage which has a genetically inheritableability to delay inactivation by an animal's host defense system, incombination with a pharmaceutically acceptable carrier.
 29. Thepharmaceutical composition according to claim 28, wherein saidcomposition is an aerosol formulation for administration to an animal'slungs.
 30. The pharmaceutical composition according to claim 28, whereinsaid bacteriophage is in lyophilized form.